Solar power plants, typically include multiple power generation sites, each of which may include one or more solar power generation devices. The electrical power generated at the multiple power generation sites is typically transmitted to a desired location or to a power grid at one or more locations.
A power generation site for a photovoltaic (“PV”) solar power plant may include a power conversion station having multiple PV solar panels connected to an inverter. The PV panels generate electrical power as direct current (“DC”) electricity. The inverter receives electricity generated by the PV solar panels as DC electricity. The DC electricity generated by the PV solar panels may be amplified or otherwise modified before it is transmitted to the inverter. The inverter then converts the DC electricity to alternating current (“AC”) electricity, and transmits the AC electricity to a point of common connection (commonly referred to as a “point of intersection” or “POI”) with other power generation sites in the electrical generating system.
A PV power plant typically includes numerous plant devices, such as PV panels, electrical combiner boxes, electrical inverters, trackers used to adjust PV panels, sensors, and other devices that are used in the generation of solar power. One important aspect of PV power plant is how plant devices are controlled and monitored. Conventional control system architectures for electrical generating systems typically either embed control and data aggregation functions into individual power generation devices (such as inverters), or provide this function through the use of other power electronics at the plant site, such as in the D-VAR intelligent grid systems manufactured by American Superconductor. Conventional control system architectures monitor the AC power that is provided from each power generation site, but typically do not monitor the DC power prior to its conversion to AC power.
It is desirable to have a control system for a solar power plant that provides plant-level control functions (such as control of plant devices), data acquisition functions, and interconnections between the various elements and facilities of the electrical generating system from a centralized location, which is cost effective, of relatively simple design, and scalable. It is also desirable to monitor and regulate the amount of DC power that is generated by a collection of PV panels prior to its conversion to AC power.
Embodiments described herein include various control systems for PV power plants, with a centralized control of various aspects of the electrical generating systems.